Trigger Fingers After Open Carpal Tunnel Release

Trigger finger (TF) and carpal tunnel syndrome (CTS) are common conditions often occurring together with an unclear relationship. While some studies conclude that TFs occur as a result of carpal tunnel release (CTR), others have not established a causal relationship. Our purpose was to evaluate the prevalence and timing of TF development in the same hand after open CTR in our population. This was a retrospective review of 497 patients undergoing open CTR by a single surgeon. Two hundred twenty-nine charts were analysed for age, gender, handedness, BMI, workers' compensation status, and background disease. We analysed the specific digit involved and timing to development of triggering after CTR. Thirty-one patients developed triggering after CTR (13.5%). Mean age was 52.5 (14.0) years. Follow-up ranged from 1 to 53 months with a median follow-up of 6 months (interquartile range = 2-13). The thumb was the most common to trigger (42.22%), followed by the ring 24.44%, middle 22.22%, little 8.89%, and index fingers 2.22%. Trigger thumb occurred at 3.5 months (3.6) post-operatively, while other digits triggered at 7.5 months (4-10.25) after surgery (P = .022). No risk factors were associated with TF development. Our results suggest that a trigger thumb develops more frequently and earlier than other trigger digits after an open CTR. Further study is needed to clarify the mechanisms involved and may enable specific treatment such as local anti-inflammatory medication following CTR. We suggest educating prospective carpal tunnel surgery patients to high risk of triggering following CTR.